Condenser-ignition device with a vacuum discharge tube joined in parallel to the ignition condenser

ABSTRACT

The invention relates to a condenser-ignition device with a vacuum discharge tube which is joined in parallel to the ignition condenser together with, in series, an electrical valve, e.g. a Zener diode or the like, which becomes current conductive the moment the ignition voltage reaches the condenser. The ignition device is provided with a mechanical contact for the firing of shots.

United States Patent Kurt Lehmann Sythen;

Gunther Kaminski, Haltem, Germany 211 AppLNo. 769,160

[72] lnventors [22] Filed Oct. 21, 1968 [45] Patented Jan. 5, 1971 [73]Assignee Wasag-Chemie Aktiengesellschaft Essen, Germany a corporation ofGermany [32] Priority Nov. 14, 1967 [33] Germany [31 No. 1,613,967

[54] CONDENSER-IGNITION DEVICE WITH A VACUUM DISCHARGE TUBE JOINED INPARALLEL TO THE IGNITION CONDENSER 3 Claims, 1 Drawing Fig.

[52] US. Cl 307/110, 320/1 [51] Int. Cl H02m 3/18 [50] Field of Search320/ 1; 323/222;321/16; 367/110 [56] References Cited UNITED STATESPATENTS 3,308,373 3/1967 Shaum 323/22 FORElGN PATENTS 951,556 3/1964Great Britain 323/22 1,126,980 4/1962 Gennany 307/110 PrimaryExaminer-Terrell W. Fears Anomey-Hammond & Littell ABSTRACT: Theinvention relates to a condenser-ignition device with a vacuum dischargetube which is joined in parallel to the ignition condenser togetherwith, in series, an electrical valve, e.g. a Zener diode or the like,which becomes current conductive the moment the ignition voltage reachesthe condenser. The ignition device is provided with a mechanical contactfor the firing of shots.

VPATENTEDJAN 519?: 3,553,480

I I E I 2 INVENTORS Kym LEHMANN Y GUNTHER mmmsm ATTGRNEVSCONDENSER-IGNITION DEVICE WITH A VACUUM DISCHARGE TUBE JOINED INPARALLEL TO THE IGNITION CONDENSER THE PRIOR ART An electrical ignitiondevice for the firing of ignition circuits of high ignition impulseenergy is known (German Pat. No. 1,126,980), in which the ignitioncondenser is joined in parallel to the terminals of the ignition circuitand where, furthermore, a vacuum discharge tube is joined in parallel tothe condenser and the terminals. In this known device the releasing ofthe shot is caused by the shutting of a contact between the condenserand one of the terminals.

Furthermore, ignition devices are known in which the mechanical contactwhich causes the release of the shot is operated by a relay (U.S. Pat.No. 2,892,128; Gennan Pat. No. 1,130,745). The disadvantage of suchignition devices with charging voltage limitations and the firing of theshots by means of a relay is that part of the charging energy is used upby the relay. Moreover, the mechanical relays are interference prone.They have a certain weight and require a certain space which again isdisadvantageous, particularly in portable condenser-ignition deviceswhich constitute the majority of all the devices.

OBJECTS OF THE INVENTION An object of the present invention is theobtention of a condenser-ignition device with a vacuum discharge tubejoined in parallel to the ignition condenser which is free of the abovedefects.

Another object of the present invention is the obtention in acondenser-ignition system for detonator ignition of propellant and/orexplosive charges, said system comprising a condenser discharge ignitioncircuit with a vacuum discharge tube joined in parallel thereto, analternating current source of electrical energy for condenser chargingand a mechanical contact for firing the shot, the improvement whichcomprises an electrical valve joined in series with said vacuumdischarge tube, which electrical valve upon the reaching of the ignitionvoltage on the condenser becomes current conductive, to form astabilization circuit for the voltage built up in said condenserdischarge ignition circuit and at least one rectifier diode joinedbetween said stabilization circuit and the ignition condenser in saidcondenser discharge ignition circuit.

These and other objects of the invention will become more apparent asthe description thereof proceeds.

DESCRIPTION OF THE INVENTION The invention is an improvement in thecondenser-ignition devices of the above-indicated type which are knownat present, in such a way that the ignition device can be built lighter,smaller, safer and cheaper.

To solve this problem according to the invention an ignition device ofthe above-indicated type is provided with an electrical valve in theform of at least one Zener diode or the like in such a way that at leastone vacuum discharge tube is joined thereto in series and that the valveand the tube are joined in parallel to the ignition condenser andfurthermore that between the thus formed stabilization chain and theignition condenser, at least one rectifier diode is joined. The Zenerdiode becomes current conductive after achievement of the ignitionvoltage across the ignition condenser. The voltage which builds up atthe vacuum discharge tube causes the tube to light up and thus indicatesthat the ignition device is ready for operation.

If, in spite of the'lighting of the vacuum discharge tube, thealternator is further operated, no voltage higher than the predeterminedvoltage can build up across on the ignition condenser since thestabilization circuit formed by the vacuum discharge tube and the Zenerdiode effects a voltage limitation. The rectifier diode on its partprevents a reduction of the voltage of the charged ignition condenserthrough the stabilization circuit.

The drawing shows an example of the circuit system of thecondenser-ignition device of the invention.

The alternating current voltage supplied by the alternator C isrectified across a voltage doubler consisting of the condenser H and thetwo rectifiers G and F. Thereafter, it charges the ignition condenser D.Joined in parallel to this condenser D are two Zener diodes A and A towhich is joined in series a vacuum discharge tube B. The vacuumdischarge tube 8 and the Zener diodes A, and A are connected in parallelto the condenser D and form a stabilization circuit for the voltagewhich is to be built up in the ignition condenser D.

In order to prevent the voltage in condenser D from decreasing afterreaching the ignition voltage in the condenser D due to thestabilization circuit A A B, a rectifier diode E is provided betweenthis circuit and the ignition condenser D.

A pushbutton T serves for the firing of the shot. This pushbutton Tcauses the ignition circuit to close the moment this button is pushed.The resistance R which is joined in parallel to the terminals or bindingposts K, and K serves to discharge the ignition condenser D when theignition machine is operated with open terminals, that is, when nodetonator circuit is connected.

In order to be able to determine the charge condition of the ignitioncondenser D in the event where a longer period of time elapses betweenthe first actuation of the alternator C and the actual firing of theshot, it is sufficient to operate the alternator C for a short period oftime which causes the glow tube B of the stabilization circuit to lightup.

The preceding specific embodiment is illustrative of the practice of theinvention. It is to be understood, however, that other expedients knownto those skilled in the art may be employed without departing from thespirit of the invention.

We claim:

1. A condenser-ignition circuit for detonator ignition of propellantand/or explosive charges consisting essentially of a means forgenerating high voltage comprising an alternating current source ofelectrical energy and a rectifying voltage doubler circuit, a seriesconnection having a vacuum discharge tube and an electrical valve joinedin parallel to said rectifying voltage doubler circuit, said electricalvalve upon reaching of the ignition voltage becoming current conductiveand ensuring a constant voltage drop independent of the cur-, rentflowing therethrough, said series connection predetermining saidignition voltage as a stabilized reference voltage, a discharge'condenser connected in parallel to said series connection through atleast one rectifier diode, preventing discharge of said condenserthrough said series connection,

discharge terminals, and'a mechanical contact for electricallyconnecting said condenser to said discharge terminals.

2, The condenser-ignition system of claim 1 wherein said electricalvalve is at least one Zener diode.

3. The condenser-ignition system of claim 2 wherein two Zener diodes arejoined in series with said vacuum discharge tube. 1

1. A condenser-ignition circuit for detonator ignition of propellantand/or explosive charges consisting essentially of a means forgenerating high voltage comprising an alternating current source ofelectrical energy and a rectifying voltage doubler circuit, a seriesconnection having a vacuum discharge tube and an electrical valve joinedin parallel to said rectifying voltage doubler circuit, said electricalvalve upon reaching of the ignition voltage becoming current conductiveand ensuring a constant voltage drop independent of the current flowingtherethrough, said series connection predetermining said ignitionvoltage as a stabilized reference voltage, a discharge condenserconnected in parallel to said series connection through at least onerectifier diode, preventing discharge of said condenser through saidseries connection, discharge terminals, and a mechanical contact forelectrically connecting said condenser to said discharge terminals. 2.The condenser-ignition system of claim 1 wherein said electrical valveis at least one Zener diode.
 3. The condenser-ignition system of claim 2wherein two Zener diodes are joined in series with said vacuum dischargetube.